var street = user.address?.street
var fooValue = myForm.querySelector('input[name=foo]')?.value

obj?.prop;
obj?.[expr];
func?.(...args);

a?.();
a?.[++x];
a?.b.c(++x).d;
a?.b[3].c?.(x).d;
(a?.b).c;
delete a?.b;

a?.b[3].c?.(x).d.e?.f[3].g?.(y).h;
